Knurling device



9 R. G. LE TOURNEAU 2,338,186

KNURLINC DEVICE Filed June 23, 194? 2 She ets-Sheet 1 HTTVS Jan. 4, 1944. R. 6. LE TOURNEAU 3 KNURLING DEVICE Filed June 23,1942 2 $heets-Sheet 2 INVENTOR R. 6'. Le Yburneau,

Patented Jan. 4, 1944 UNITED STATES PATENT OFFICE KNURLING DEVIGE Robert G. Le Tourneau, Peoria, 111., assignor to R. G. Le Tourneau, Inc., Stockton, Califi, a corporation of California Application June23, 1942, Serial No. 448,093

3 Claims.

This invention is directed to an improved knurling device for metal members, and in particular the invention comprises, and it is the principal object to provide, a unique knurling device arranged to be mounted on a lathe for use to knurl a peripheral path on a cylindrical member chucked in the lathe and driven thereby; the device being especially designed to effect a knurling operation in the bottom of the band seat or groove of an ordnance shell during manufacture of the latter.

It is also an object of this invention to provide a toothed knurling wheel which is so formed that after one complete knurling operation about the cylindrical member, the knurling wheel automatically disengages from the work without attention by the operator; this being accomplished by employing a knurling wheel having a peripheral portion which is smooth and of reduced diameter, whereby when the toothed portion of the wheel-which is of a length substantially equal to the circumference of the work being knurled runs out relative to said work, the knurling wheel is freed therefrom.

A further object of this invention is to provide a knurling device which includes a hand actuated swinging yoke arranged to be mounted in connection with the bed of a lathe; the yoke carrying a knurling wheel which projects beyond the free or outer end of said yoke for engagement with the work upon swinging movement of said yoke to a predetermined position.

A futher object of the invention is to produce a simple and inexpensive device and yet one which will be exceedingly eiiective for the purpose for which it is designed.

These objects I accomplish by means of such structure and relative arrangement of parts as will fully appear by a perusual of the following specification and claims.

In the drawings similar characters of reference indicate corresponding parts in the several views:

Figure l is an end view of the knurling device as engaged with a rotating cylindrical member; the non-working position of the device being shown in dotted lines.

Figure 2 is a front elevation, partly in section, of the device in working position.

Figure 3 is a fragmentary end view showing the knurling wheel as set to the starting position, taken from the end opposite Fig. 1.

Figure 4 is a fragmentary end view partly broken away, illustrating the knurling wheel and work immediately prior to completion of a knurling revolution thereof, taken from the same end as Fig.1.

Referring now more particularly to the characters of reference on the drawings, the numeral I indicates a cylindrical member, here'shown as an ordnance shell, chucked in a lathe headstock 2 and rotated by the latter. In the manufacture of ordnance shells a band seat or groove 3 is machined in the shell adjacent the rear end thereof; said band seat'having annular ridges or ribs 4 upstanding from the bottom thereof. Before the band (not shown) is press-fitted into the band seat 3, the rings 4 are knurled to subsequently form a lock between the press-fitted band and the shell for the purpose of preventing rotation of said band in the band seat.

The knurling device comprises ,a flat base 5 adapted to be secured by suitable means, such as securing bolts l, in connection with the bed 6 of the lathe below the work I. Parallel upstanding ears 8 are fixed on the base 5 in spaced relation lengthwise of the lathe; said ears terminating at their upper end some distance short of the work I.

A swinging yoke 53 ispivoted between the ears 8 on a cross pin Iii; said pin being in ahorizontal plane below and forwardly offset relative to the vertical center line of the work, and the outer end of the yoke projecting some distance beyond the corresponding ends of the ears 8. 1

A knurling wheel I I is affixed on another cross pin I2 which is journaled by bearings I3 in the legs of yoke 9; one end of pin I2 being headed, as at I4, and the other end being threaded for the reception of a securing nut I5. Theknurling wheel II is of such diameter that the periphery of said wheel extends beyond the outer end of the yoke; said periphery of the wheel for a major portion of its length being toothed as at I6. This toothed portion of the periphery of the knurling wheel is of a length substantially equal to the circumference of the work (ribs 4) to be knurled. A relatively short portion I! of the periphery of the knurling wheel is smooth and of reduced diameter for the purpose which will hereinafter appear.

The swinging yoke 9 is fitted with a handle I8 which projects therefrom at an upward and outward slope at right angles to the axis of pin I0; the pins Ill and I2 being parallel to the axis of the lathe. On the side opposite handle I8 one of the ears is arranged with an adjustable stop bolt I9 which limits swinging movement of yoke 9 and controls the depth which the knurling wheel cuts into the work.

In order to properly locate the knurling wheel relative to the work at the outset of a knurling operation, a stop pin 20 projects from the head I 4 (which rotates with wheel I l) near the periphery thereof. A lug 2! is secured on the adjacent member of yoke 9 so as to project into the path of the pin; said pin and lug being disposed relative to the smooth or untoothed portion of wheel so that when the pin is engaged with the leading side of the lug, said smooth portion is properly positioned relative to the work to start a knurling operation.

Operation In operation, the knurling device is normally clear of the work, as is shownindotted lines in V Fig. 1; the knurling wheel being radially alined' with the band seat 3 of the shell I. When the operator desires to efiect a knurling operation, he grasps handle it and raises the same, causing the yoke to swing upwardly. He also turns wheel II by means of pin 2% so as to engage said pin with lug 2| as above stated, so that when the yoke engages stop bolt l9 and the yoke is beyond dead center of the weight of the yoke and the wheel I I acting vertically on the cross pin it, the

' smoother reducedpo-rtion I! of the wheel l i is below the work with the adjacent endmost teeth clear ofthe ribs 4.

The operator thenmanually imparts a slight rotation to wheel H in the direction indicated by the arrow in Fig. 1. The first tooththen en- 'gages the rings 4 adjacent but slightly ahead of "the low point ofsaid rings, and the knurling wheel' begins its cutting'operation; being driven from the rotating work.

After the work has made one complete revolution, the ribs dare knurled for their entire length and' at substantially this time the knurling wheel reaches the end of its toothed portion and the work escapes from said' portion, as indicated in Fig. 4. 'The' pin 20 then engages the opposite side of'lug 2 I, preventing further rotation of the wheel 'in a knurling direction and a possible rec'at'ching 'ofthe teeth against the ribs. The wheel must 'then' be manually rotated in a reverse direction to start a subsequent knurling operation; It will thusbe seen thatb'y use of the reduced diameter and smooth portion I! and the stop means, the

knurling wheel can make only one revolution with the'work, as isdesirable'to prevent retracking of the Wheel on the work and. possible undesirable results.

When a knurling operation has been completed,

' the operator grasps handle IBand pushes down on the same, which results in the yoke 9 and the knurling wheel I l swinging clear of the work and to the non-working position shown in dotted lines in Fig. 1.

From the foregoing description it will be readily seen that I have produced such a device as substantially fulfills the objects of the invention as set forth herein.

While this specification sets forth in detail the present and preferred construction of the device, still in practice such deviations from such detail may be resorted to as do not form a departure from the spirit of the invention, as defined by the appended claims.

Having thus described my invention, what I claim as new and useful and desire to secure by Letters'Patent is:

1. A knurling device for cylindrical work chuckedin a lathe, comprising a manually swingable support pivoted in connection with the lathe for swinging movement transversely of the work, a knurling wheel journaled on the support and projecting therebeyond, and a stop against which the support rests when the knurling wheel is in work engaging position; said support being mounted on the lathe in such relation to the work and to said stop that said support when resting against the latter tends to remain in such position, the knurling wheel being circular and having teeth projecting from a portion only of its periphery, and the toothed portion of said wheel being of a predetermined length relative to the diameter of the work.

' 2. A knurling device for cylindrical work chucked in a lathe, comprising a manually swingable support'pivoted in connection with the lathe forswinging movementtransversely of thework,

a knurling wheel journaled on the support and projecting therebeyond, and a stop against which the support rests when theknurling wheel is in "work engaging position; said support being mounted on the lathe in such relation to the work and to said stop that said support when'resting against the latter tends to remain in such Iposiof the Work.

ROBERT G. LE TOURNEAU. 

